tarsal tunnel syndrome

Definition: a syndrome resulting from entrapment of various foot nerves in the ankle region. Two distinct types are recognized: medial tarsal tunnel syndrome (TTS), characterized by pain, paresthesias, or both, experienced on various portions of the sole of the foot, due to injury of the medial plantar, lateral plantar, or medial calcaneal nerves in or near the tarsal tunnel on the medial aspect of the ankle; and anterior tarsal tunnel syndrome, which involves the distal portion of the deep peroneal nerve, distal to the ankle; it is usually asymptomatic and diagnosed by peroneal motor nerve conduction studies. Unless otherwise stated, the term tarsal tunnel syndrome refers to medial tarsal tunnel syndrome.